Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Far Away Galaxy Under The Microscope

17.08.2006
SINFONI Discovers Rapidly Forming, Large Proto-Disc Galaxies Three Billion Years After The Big Bang

An international group of astronomers have discovered large disc galaxies akin to our Milky Way that must have formed on a rapid time scale, only 3 billion years after the Big Bang. In one of these systems, the combination of adaptive optics techniques with the new SINFONI spectrograph on ESO’s Very Large Telescope (VLT) resulted in a record-breaking resolution of a mere 0.15 arcsecond, giving an unprecedented detailed view of the anatomy of such a distant proto-disc galaxy.

“We have been able, for the first time, to obtain well resolved, two dimensional images of the gas motions in distant star forming galaxies, whose light has traveled more than 11 billion years to the Earth,” said Reinhard Genzel, lead author of a paper in this week’s issue of Nature in which these results are presented.

This tells the story how galaxies looked like a mere 3 billion years after the Big Bang.

Over the past decade astronomers have established a global framework of how galaxies formed and evolved when the Universe was only a few billion years old. Gas of ordinary matter cooled and collected in concentrations of the mysterious ‘dark’ matter (so called dark matter halos). Since that time and up to the present epoch collisions and mergers of galaxies subsequently led to the hierarchical build-up of galaxy mass. This general picture leaves open, however, on what timescales galaxies were assembled and when and how bulges and discs, the primary components of present day galaxies, were formed.

A major study of distant, luminous star forming galaxies at ESO’s VLT, the ‘SINS’ (Spectroscopic Imaging Survey in the Near-Infrared with SINFONI) survey, has now resulted in a major break-through on these questions. This study exploited SINFONI [1], a novel infrared ‘integral field spectrometer’ that simultaneously delivers sharp images, with adaptive optics, and highly resolved colour information (spectra) of an object on the sky.

In the case of the galaxy BzK155043 at cosmological redshift 2.4, the SINFONI observations achieved an angular resolution of 0.15”, a mere 4000 light years at the distance of this high redshift galaxy. With this superior angular resolution the data reveal the physical and dynamical properties in unprecedented detail. Surprisingly the observations reveal a large and massive rotating proto-disc that is channeling gas toward a growing central stellar bulge. The high gas surface densities, the large star formation rate and the moderately young stellar ages derived from these observations suggest that the system was assembled rapidly, by fragmentation and star formation in an initially very gas rich proto-disc. SINS observations of several other massive, high redshift galaxies give similar results.

“When we started the SINS programme,” said Genzel, “we expected to see mostly irregular and perhaps even chaotic motions caused by the frequent merger activity in the young Universe. We were in for a major surprise when we found a number of large, rotating and gas rich disc galaxies whose properties are quite similar to the present day Milky Way”.

The fact that these galaxies are so large and rotate rapidly indicates that the gas has a similar amount of rotation as the dark matter halo from which it cooled, thus empirically solving an important question of galaxy formation.

Natascha Förster Schreiber, lead author of another recent SINS paper in the Astrophysical Journal said: “We now need to understand how these early proto-discs evolved subsequently in time. Our suspicion is that they might not have been stable.”

The SINFONI data suggest that the proto-discs may have eventually been transformed to dense elliptical galaxies, either by internal processes, such as the spectacular gas inflows observed in BzK15504, or by collisions and mergers with other galaxies, which were frequent in the dense environments in which the high redshift luminous star forming galaxies appear to reside in.

Another important aspect of the work are the very high star formation rates deduced for many of the luminous star forming high redshift galaxies, about one hundred times greater than in the present-day Milky Way.

“We have a growing body of evidence that massive galaxies formed much more rapidly in the redshift range 2-3 than originally anticipated,” said Andrea Cimatti, team member from the University of Bologna. “The new SINFONI data give us a first glimpse what processes might be involved.”

The SINS programme on the VLT is a stunning demonstration of what is going to be possible in the next few years with the combination of integral field spectroscopy and adaptive optics.

Henri Boffin | alfa
Further information:
http://www.eso.org/outreach/press-rel/pr-2006/pr-31-06.html

More articles from Physics and Astronomy:

nachricht Significantly more productivity in USP lasers
06.12.2016 | Fraunhofer-Institut für Lasertechnik ILT

nachricht Shape matters when light meets atom
05.12.2016 | Centre for Quantum Technologies at the National University of Singapore

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

How to turn white fat brown

07.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>